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Date: Wed, 19 Sep 2007 16:44:10 -0400 (EDT)
From: Stuart Anderson <anderson@netsweng.com>
Subject: Re: [Qemu-devel] RFC: [0/11] EFAULT patch
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To: qemu-devel@nongnu.org

On Wed, 19 Sep 2007, Paul Brook wrote:

> No. We're doing more than most 32-64 syscall thunks. To a first approximation
> the syscall thunks can bindly zero extend all values. In qemu we need to know
> whether something is a pointer or a value.

Isn't that was the code in do_syscall() does? or am I looking at something
in the wrong way?

> Kernel and userspace addresses are not interchangeable in the kernel. Any
> place that does so is probably a bug.

I said co-exist, not interchangeable. My point was that the 32-on-64
code didn't do any explicit mapping of pointers passed to it other than
the normal API.

I'm having trouble determining how you would like for things to be. Could
you maybe provide a small sample of how all of this should work, and then
I can probably see what I'm not quite getting.


                                 Stuart

Stuart R. Anderson                               anderson@netsweng.com
Network & Software Engineering                   http://www.netsweng.com/
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